U.S. Pat. No. 3,224,500 discloses a floor panel which is reinforced on its under side by a plurality of laterally spaced metallic longitudinal ribs. The floor panel is preferably made from extruded members so that the ribs are integrally formed with the top sheet. The floor panel rests upon a plurality of elongated transverse support elements. These transversely extending support elements are spaced apart longitudinally of the vehicle. The transversely extending members are in turn supported by a plurality of longitudinal stringers extending longitudinally of the vehicle body and spaced apart transversely of the body. Stringers rest upon and are supported by metallic cross beams which in turn transmit the entire weight of the cargo to the trailer longitudinal frame.
U.S. Pat. No. 4,091,743 discloses a plurality of modular units formed of ducts and horizontal load-supporting webs each forming part of a ventilating floor structure with the ducts and webs being interconnected to adjacent modular units for forming a total floor. The ducts have upwardly diverging sidewalls for strength and a duct of one modular unit is provided with a bead that forms half of a joint to be slid within a downwardly opening recess forming the other half of the joint on an adjacent web. The recess is provided with a downwardly and laterally curving guide flange so that the bead can be rolled into the recess as the modular unit having the bead is rotated into position. The interconnected ducts and webs are underlayed with foam insulation which is carried up into each web for additional insulating thickness the joint is essentially waterproof from water passing into or through the ducts.
U.S. Pat. No. 6,082,810 discloses a cargo floor construction and method of constructing same that includes a multiplicity of mounting clips that are secured to the cargo vehicle support members in laterally spaced and longitudinally aligned rows. The mounting clips are provided with a shape for mating and interlocking with the lateral edges of longitudinally extending floor planks that preferably are extruded with the mating edge shapes. Fasteners are used to secure the mounting clips to the vehicle support members but those fasteners do not pierce the floor planks. In some embodiments of the interlocking mounting clips and floor plank edges, the floor plank is elastically deformed to engage or snap onto the mounting clip to prevent lateral movement of the floor plank in either direction.
U.S. Pat. No. 7,963,410 discloses a container floor plate, in particular for a refrigerated container, with an upper floor layer, a lower floor layer and an intermediate insulating layer, support blocks being located between the upper floor layer and the lower floor layer. The purpose of the invention is to obtain a good insulation with a small mass. For this purpose, the lower floor layer is provided with several transversal supports, each support block being supported on a transversal support.